(Over)lap the car

To blur the back­ground with­out af­fect­ing the car, we need an over­lap around its edges. Grab the Clone tool, hit 0 for 100% opac­ity, Alt-click to tar­get an area of back­ground next to the edge of the car, then paint to add an over­lap all the way around. It doesn’t need to be per­fect.